Ariz. Rev. Stat. § 11-114
Santa Cruz county, the county seat of which is Nogales, is bounded as follows:
Commencing on the international boundary line between the United States and the Republic of Mexico, at the point where the eastern line of range eighteen east of the Gila and Salt River Guide meridian touches the international boundary line; thence north along the eastern line of range eighteen east to a point where said line intersects the south boundary line of the San Ignacio del Babacomari land grant; thence east along the south line of said land grant approximately one-half mile, to a point due south of the intersection of the east line of range eighteen east with the north boundary line of the San Ignacio del Babacomari land grant; thence north through the aforesaid intersection point on the north line of said land grant along the eastern line of range eighteen east to a point six miles north of the fourth standard parallel south; thence due west forty-two miles to the intersection of the line between ranges eleven and twelve east, such point being near the Bustamante ranch as it existed in the year 1899 on Sopori creek; thence due south fourteen miles; thence due west twelve miles to a point; thence due south to said international boundary line; thence easterly along said international boundary line to the place of beginning.
A.R.S. § 11-114